Varnish

Varnish Cache is a web application accelerator also known as an HTTP accelerator. You can install it in front of any server that speaks the HTTP protocol and configure it to cache the content. Varnish Cache is very, very fast and will improve your site's loading speed. One of the essential virtues of Varnish Cache is the flexibility of its configuration language, VCL, which permits you to specify how incoming requests should be tackled.

Memcached

Memcached is a generic distributed memory caching system for boosting the loading speed of dynamic database-powered web sites. It is used to decrease the number of times an external data source (such as a DB or API) is read by caching data and objects in RAM. The Memcached distributed memory caching system uses a client/server architecture. The Memcached distributed memory caching system is used by some of the most traffic-intensive websites on the World Wide Web and is supported by popular web apps like Joomla and WordPress.

Node.js

Node.js is a software system for writing highly scalable Internet applications. Built on Chrome's JavaScript runtime, Node.js uses an event-driven, asynchronous input/output model that makes it lightweight and effective, excellent for high-performance content-rich network apps. Node.js uses Google's V8 JavaScript engine, libUV, and a number of in-built libraries.

InnoDB

InnoDB is the default database engine for the MySQL open-source database management system. A storage engine is the principal software component that a DBMS uses to create, read, update and delete data from a database. The latest release of InnoDB features considerable improvements in efficiency, dependability and usability. InnoDB provides the standard ACID transaction properties, as well as declarative referential integrity support. InnoDB is included as standard in most binary distributions from MySQL AB.